A variety of joints is used in the angular connection of hollow profile members with their edges being cut at an angle of 45° and brought in matching contact to form door or window frames, partitions or other applications. The hollow profile members are cut at an angle of 45° in each corner of the generally rectangular frame of either the frame profile member that is fixedly mounted onto the wall surrounding a door or window opening or of the sash profile member operationally mounted therein. A joint item is thereafter being introduced within abutting chambers of a pair of hollow profile members being brought in matching contact at each one of the corners of the aforementioned generally rectangular frame, the joint providing a stable connection of such profile members.
Prior art joints generally comprised spring activated button means detachably engaging into suitable apertures provided at the corners of the hollow profile members being connected, such joints being adapted to stabilize the angular connection thereof. These prior art joints required, prior to employment thereof, the opening of apertures at accurately selected locations of the hollow profile members wherein are engaged the abovementioned spring activated buttons. This process is awkward and time consuming due to the accuracy required in marking and drilling of the apertures and often leads to an imperfect fit of the profiles and to a structure of reduced aesthetics and functionality due to the erroneous alignment of the hollow profile members brought in matching contact or to a loosening of tightening of the joint in the course of time.
WO 2004/033837 of Athanasios Leontaridis discloses a joint for the angular connection of frames for doors and windows, such joint comprising a slide base portion with side parts inserted within the abutting chambers of a pair of hollow profile members being connected and an analogously configured sheet metal mobile portion superimposed thereupon, the sheet metal mobile portion including upwardly extending legs with indenting edges, a bolt passing through a single hole that is required in this disclosure, ach bolt being employed in the tightening process of the joint, wherein after the joint has been inserted into the hollow profile members being brought together for connection, the bolt acts so as to exert an upwardly raising force onto the sheet metal mobile portion, whilst maintaining the slide base portion at a fixed position, and subsequently leading the sharp indenting edges of the sheet metal portion to produce an indentation effect into the walls of the corresponding chambers of the hollow profiles being angularly connected with the joint, as the bolt is being tightened, thereby resulting in a robust, self aligned connection of the hollow profile members. The hereinabove angular joint disclosed in WO-2004/033837 with its symmetrical arrangement on either side of a plane of symmetry passing though the plane of matching contact of the hollow profile members being connected has contributed in overcoming the aforementioned problems of joints of the prior art, since it substantially facilitates the user, i.e. the technician who assembles doors or windows through angularly connecting previously cut profile lengths to produce the frames, which must subsequently filled, e,g, with a glass panel or a shutter. The user is in particular facilitated due to the requirement of a single handily marked and drilled hole in place of the plurality of holes posing awkward precision marking and drilling requirements in the angular joints of the prior art, thereby providing a decreased cost in the usage thereof. Furthermore, the joint disclosed in WO-2004/033837 has provided a strong and reliable connection that in the course of time is much less vulnerable in preserving its high standard of performance.
However, whilst the hereinabove described joint that was disclosed in WO 2004/033837 has had a warm international welcome, the extensive use thereof highlighted a drawback related to its use for the angular connection of hollow profile members of relatively larger dimensions, wherein the upwardly bent sections of the sheet metal mobile portion being adapted to indent the walls of the chambers of the hollow profile members being connected have to extent at a long distance thereby resulting in a deficient and uncertain indentation of the sharp edges thereof into the walls of the chambers of the hollow profile members being connected.
It has in particular been established that certain geometrical parameters applicable in the manufacturing of the joint that specifically relate to the slope of the upwardly extending members of the sheet metal mobile portion and of the geometry of impact thereof onto the walls of the hollow profile members being indented do play a significantly important role in achieving an optimum indentation into the walls of the hollow profile members being connected. An important role is also played by the angle formed by the wall of the chambers of the hollow profile members being connected onto which is mounted the base portion of the joint with a straight line passing through a terminal point E1 of contact of the inwardly bent side surface of the sheet metal mobile portion with the section surface of the base portion prior to the upward bending thereof into the upwardly extending member and through a point E2 of impact of the upwardly extending member of the sheet metal mobile portion onto the opposing wall of the chambers of the hollow profile members being connected. The angle formed by the wall of the hollow profile members being indented with a line transversally crossing the indenting edge of the sheet metal mobile portion is also important. It has further been observed that the aimed indentation of the edges of the sheet metal mobile portion onto the walls of the aforementioned chambers is deficient because of an aberrant sharp edge thereof that is being created at one side of a terminal edge of the sheet metal during the cutting process from a sheet metal web.
It is therefore an object of this invention to provide advantageous modifications of the joint disclosed in WO 2004/033837 with a scope of addressing the abovementioned disadvantages and shortcomings through the disclosure of new features of the slide base portion and of the sheet metal mobile portion superimposed thereupon and of certain geometrical parameters thereof so as to improve and to strengthen the capacity of the upwardly extending members of the sheet metal mobile portion to achieve an efficient indentation of the walls of the chambers of the hollow profile members being connected regardless of the dimensions of the latter.
This object of the invention is achieved by optimizing the design and the orientation of the sheet metal mobile portion as will be described in detail hereinafter:
a) providing the slide base portion with upwardly bent terminal side surfaces, thereby forming sockets on either side thereof appropriately configured for nesting the equivalently bent terminal side surfaces of the sheet metal mobile portion.
b) treating the sharp edges of the sheet metal mobile portion following cutting thereof from a sheet metal web with a scope of alignment in the longitudinal direction of the sheet metal mobile portion of an aberrant sharp edge resulting from the cutting blade having been driven perpendicularly into the web of the sheet metal, thereby obtaining an appropriate form of the sharp edges that would facilitate indentation of the walls of the hollow profile members being connected.
c) selectively orienting the upwardly bent members of the slide base portion and of the sheet metal mobile portion with a scope of complying with certain predetermined geometrical parameters to be described hereinafter, including providing the sheet metal mobile portion with a zigzag extension of the upwardly bent member thereof in the case of use of the joint in the connection of hollow profile members having chambers with larger dimensions.
Additionally or alternatively, the above object is being achieved through use of a slide base portion that advantageously approaches the region of the walls in the chambers of the hollow profile members being connected wherein the indentation of the sheet metal mobile portion takes place, such effect being obtained with the employment of an elevated slide base portion that achieves rapprochement of the walls of the chambers intended to be indented by the sheet metal mobile portion, the same result being alternatively achieved by using the standard slide base portion in combination with an additional base raising member provided with legs adapted to raise the slide base portion at a desired level for the sheet metal mobile portion to effect an efficient indentation of the walls of chambers of the hollow profile members being connected, as well as by using a specially configured slide base portion of the type of joints being used in association with a mechanical press assembly comprising cutting blades used to cut strips of material of the walls of the hollow profile members being connected and embed such strips within specially configured recesses on either side of the slide base portion. This last method of connection of hollow profile members to form frames for doors and windows as used in the prior art requires the single element of the joint to have side arms that firmly fit within the chambers of the hollow profile members being connected and are glued therein prior to employment of the mechanical press assembly and as a result a poor performance thereof might result from use of the press assembly and embedding of the aforementioned strips before the glue has adequately dried. Further this method of angular connection of profiles necessitates use of joints of varying sizes to fit chambers of correspondingly varying sizes, thereby increasing costs.
It is therefore a further object of the invention to propose an embodiment of the joint of the invention wherein the slide base portion is provided with side parts firmly fitted within chambers of the hollow profile members being brought in matching contact and a sheet metal portion with indenting sides is superimposed thereupon, whereby the employment of the mechanical press assembly that is used in the prior art with a scope of cutting strips of material of the walls of the chambers to embed them within recesses of the joint or the use of glue to stabilize the connection is merely an optional choice and not a necessary requirement.
These and other objects, characteristics and advantages of the present invention over the prior art will become apparent in the detailed description hereinbelow.